Radiographic film cassette

ABSTRACT

A radiographic film cassette suited for being used in combination with a daylight unloading system is presented. It comprises a cover and a bottom frame which are hingedly connected to each other in such a way that not only a rotation at the hinges occurs, but also a lifting up of the cover near the hinges. In this way the sheet of X-ray material becomes completely free. Further, two deformable pins are provided in the bottom part in order to permit the air to flow under the sheet, avoiding thereby a sticking of the latter to the screens. The cassette is advantageously used with a simple unloading device, placed in front of the entrance slit of a processing machine; the unloading device itself may be supplementarily equipped with means to print identification data on the sheet of X-ray material.

Stievenart et al.

[451 Sept. 17, 1974 RADIOGRAPHIC FILM CASSETTE Inventors: Emile FransStievenart, Hoboken;

Leo Paul Van Bouwel, Mortsel; Hendrik Sylvester Plessers, Boechout, allof Belgium Agfa-Gevaert N.V., Mortsel, Belgium Filed: Dec. 27, 1972Appl. No.: 319,062

Assignee:

Foreign Application Priority Data Dec. 29, 1971 Great Britain 60344/71US. Cl 250/481, 250/475, 250/476,

250/480 Int. Cl. G03b 17/26 Field of Search 250/475, 476, 480, 481

References Cited UNITED STATES PATENTS Kamiss Kamiss 250/481 2,878,3893/1959 Raffman 250/481 3,296,437 1/l967 Meschan.... 250/476 3,675,0147/1972 Perl 250/480 Primary Examiner-William F. Lindquist Attorney,Agent, or F irm-William J. Daniel [5 7] ABSTRACT A radiographic filmcassette suited for being used in combination with a daylight unloadingsystem is presented. It comprises a cover and a bottom frame which arehingedly connected to each other in such a way that not only a rotationat the hinges occurs, but also a lifting up of the cover near thehinges. ln this way the sheet of X-ray material becomes completely free.Further, two deformable pins are provided in the bottom part in order topermit the air to flow under the sheet, avoiding thereby a sticking ofthe latter to the screens. The cassette is advantageously used with asimple unloading device, placed in front of the entrance slit of aprocessing machine; the unloading device itself may be supplementarilyequipped with means to print identification data on the sheet of X-raymaterial.

7 Claims, 6 Drawing Figures PATENIED SEP 1 71914 SHEET 2 BF 5 ow ,8 NQMmm mm i Q PAIENIED SEP! 7 am sum b or 5 PAIENTEDSEPITIHH 3.836.783

v SHEET 5 [IF 5 Fig.6

1 RADIOGRAPHIC FILM CASSETTE This invention relates to a radiographicfilm cassette and more particularly to a radiographic film cassetteintended for use in an apparatus for automatically unloading thecassette and feeding the exposed X-ray sensitive sheet material into theentrance slit of an automatic processing machine.

In particular the invention concerns a cassette permitting an automaticunloading in daylight by means of simple mechanical means.

Several systems for automatically unloading X-ray cassettes in daylighthave already been described. They generally consist of magazines thattemporarily stock the cassettes to be unloaded and position them infront of an unlocking mechanism of an unloading station whereupon theexposed film sheet is gripped and intro,-

duced between a pair of rollers, guiding said film sheet over adischarge passage towards the entrance slit of an automatic processingmachine for further processing. A description of such apparatus can befound in United Kingdom Pat. Specifications 961,439 filed Jan. 12, 1961and 961,440 filed July 21, 1961 both by Gevaert Photo-Producten N.V.; acassette to be used in combination with said apparatus is described inUnited King dom Pat. Specification 961,437 filed June 30, 1960 byGevaert Photo-Producten N.V.

Although the apparatus described in the abovementioned patents suit verywell in practice when quantities of X-ray film sheets are to beprocessed, a great deal of their importance gets lost when the pro:cessing machine is only intermittently used or when decentralizedprocessing departments offer more opportunities.

The present invention aims at providing a cassette which permits adaylight unloading of the X-ray sensitive sheet material withoutnecessity of recurring to expensive or rather complicated apparatus.

The invention further aims at providing a quite simple identificationsystem, which may be used advantageously in combination with a cassetteaccording to the invention.

According to the invention the radiographic film cassette comprises twoframes which are hingedly connected to eath other by means of hingemeans at one edge and which can be locked together by means ofappropriate locking means, wherein at least one of the frames isconnected to the hinge means through a yieldable member, urging the twoframes together at their hingedly connected edges, and wherein thelocking means are so arranged that, upon opening the cassette, they arecapable of moving the two frames from each other at the correspondingedges near the hinge means over a distance which is greater than in caseboth frames were rigidly connected to said hinge means.

The construction and the working principle of the cassette will bedescribed and expalined in the light of a preferred embodiment presentedin the FIGS. 1 to 6 in which:

FIG. 1 shows a perspective view of the cassette in opened position,

FIG. 2 presents a partial view of the upperside of the closed cassette,

FIGS. 3 and 4 show the locking mechanism respectively in locked andunlocked position according to the section line 3-3 of FIG. 2,

FIG. 5 illustrates the mechanism for unloading. the cassette,

FIG. 6 shows a cross-sectional view of a preferred embodiment of anapparatus used for identification purposes in combination with thecassette according to the invention.

As can be seen in FIG. 1 the cassette consists of a bottom frame 11 anda cover 12 which are hingedly joined together by means of hinges 13 and44. A pair of intensifying screens 15 and 19v are provided at the bottom11 and the cover 12 and are supported by means of sheets of elasticmaterial 17 and 18. In the intensifying screen 19 deformable pins 40 and42 are provided in corresponding openings which lift the sheet of X-raysensitive material 41 in order to permit air to flow under it and toprevent same from sticking to said screens when opening the cassette. Apart of the front edge of the bottom plate 11 is cut away so that, whenbringing the cassette in tilted position with its front side directeddownwards, the X-ray sensitive sheet material 41 is able to slide softlythrough the opening. Said opening is masked by strips of felt or similarmaterial 16 and 29 attached to the front of both the cover and thebottom plate to secure the light-tightness of the cassette when thelatter is in locked position. Further are provided locking and unlockingmeans 20 to 28, in order to prevent an undesired opening of the cassetteduring operation, and to exert a certain pressure upon the sheet ofX-ray sensitive material 41 for maintaining a stable position duringexposure of the latter.

In order to illustrate the position of the hinges, FIG. 2 represents apartial view of the upper side of the closed cassette. The hinges 13 and44 made of spring steel are fixed to the cover by means of five rivets14 in such a way that a part sufficiently long to guarantee thenecessary resilience between the cover and the axis of the hinges ismaintained. The other part of said hinges is fixed to the bottom frameby conventional means known in the art.

FIG. 3 shows a side-view of the locking mechanism in locked positionaccording to the section line 3-3 of FIG. 2. This mechanism consists ofa sliding lath 20 provided at both sides of the cassette situatedbetween the overlapping of the cover and the bottom and joined by meansof a lath 21 to'a lever 22.

'In the sliding lath 20 two slots 23 and 33 are provided for permittingthe pins 24 and 39 fitted on the inner side of the longitudinal wall ofthe bottom frame to guide said sliding lath 20 in a manner so as to runparallel with said bottom frame. On said sliding lath 20 means arefitted for locking the cover to the bottom plate. So are provided thegrips 25 and 34 which in locked position grip the notches 26 and 38attached to the inner side of the longitudinal wall of the bottom frame.Further are provided the cams 27 and 35 which upon unlocking open thecassette by pushing upwards the pins 28 and 37 situated in the outerside of the longitudinal wall of the cover.

FIG. 4 shows the position of the locking mechanism in unlocked position.When shifting the lever 22 in the sense denoted by the arrow 30, thesliding lath 20 moves in the direction 31 releasing the notches 26 and38. Moreover, the cams 27 and 35 which have a partly slanting front sideengage the pins 28 and 37 and lift the latter in the sense of the arrows32 causing the cover to move upwards. The elasticity of part of thehinges l3 and 44 connected to the cover provides that said cover notonly performs a rotation around the axis of said hinges but alsoexecutes a vertical lifting-up movement pressure upon the sheet of X-rayfilm. The interesting advantage resulting herefrom lies in the fact thatthe rear part of the sheet of X-ray film becomes completely clear fromthe screens.

The way to use the cassette in combination with an automatic processingmachine is illustrated in FIG. 5. The cassette is introduced into a kindof tunnel 50, the upper side of it being provided at its upper extremitywith means 54 whereby one extremity of a light-tight curtain 51 is fixedto the apparatus. This curtain is spread over the cassette after thecassette has been introduced into the tunnel. Then the levers 22 and 36make contact with a corresponding resilient rabbet 52. By furtherpushing, the rabbet 52 lifts the levers 22 and 36 so that the cover 12becomes unlocked and the X-ray sensitive material 41 is forwardedtowards a pair of rollers 53 which feed it to the entrance slit of theprocessing machine. As the rabbet 52 extends over the complete width ofthe tunnel 50 and by making the light-tight curtain sufficiently long,no limitations as to the width and length of the cassettes exist and allcurrent sizes may easily and safely be used in connection with thisdevice.

As can be seen in FIG. 6, the opening station at the entrance slit ofthe processing machine may advantageously be equipped with a simpleidentifying means, that is to say, a small photographic exposure device,by means of which identification data may be exposed on the film beforeprocessing.

For this purpose, the sheet of X-ray sensitive material 41 passes underthe outlet opening of an exposure device 60 situated after the openingstations provided at the entrance of the processing machine.

The said exposure device 60 comprises a housing 61 of preferablyrectangular section which is composed of two bodies forming an anglewith each other. In the bisector plane of this angle is provided a slide62 in which data carrying means, for example a small, semitranslucentsheet of paper 63 may be slid. On sheet 63 the ncessary data may betype-written and it is introduced into the slide 62 with the datacarrying surface turned in downward direction. The vertical part of thehousing 61 is in fact a small pinhole camera, the pinhole 64 beingprovided in a screen 65.

The lighting unit 66, mounted in the housing 61 consists mainly of aflash-tube 67, provided with electrodes 68 and 69 and has an aperture 70through which radiant energy may be projected into the housing 61. Uponenergizing said flash tube 67, light is thus projected through the datacarrying means 63, now housed in slide 62, and further through pinhole64 towards the exit of housing 61, where it is absorbed on an area ofthe X-ray sheet material 41. Preferably, the exposure occurs near one ofthe edges of the X-ray sheet material 41 and particularly on an area ofthe leading edge thereof.

Exposure of supplementary data on said sheet of X-ray sensitive material41 may be done automatically in a very simple way. To this end, amicroswitch 72 is provided in the tunnel, leading to the processingapparatus. The arm 71 of said microswitch may be lifted easily by thefront-edge of the X-ray sensitive material 41, causing an internalcontact (not shown) to close, so that a switching action occurs in thepower supply station 74 of the flash tube 67. In this way, said flashtube ignites, because energy is transferred through the wires 75 to itselectrodes 68 and 69. The power supply station 74 for the flash tube 67may be of any conventional type and may be operated by battery or by themains as well. As such devices are sufficiently known by those skilledin the art, they need no further explanation.

From the foregoing, it may be concluded that a completely new daylightunloading system, together with an identification system, both ofextreme simplicity have been devised, which may be adopted for bothsmall table-top processors and high-speed processing apparatus which runfully automatically.

The need for processors to be installed, at least with their loadingside, in a darkroom is completely undone in this way. Small table-topprocessors, which are very well suited for a decentralized functioningand which may even be installed in an operating room, permit thecontinuous control during surgical activities without need for recurringto externally situated processing machines.

The scope and spirit of the invention, not being limited by theembodiment described hereinbefore, shall be derived from the appendedclaims.

We claim:

1. A radiographic film cassette comprising two generally flat boxsections, each including a wall panel with side flanges upstanding fromthe edges thereof, adapted to fit together in telescoping relation toform a generally light-tight container, one of said wall panels beingtransparent to X-ray radiation, hinge means connecting said box sectionstogether along corresponding side edges thereof, said hinge means beingyieldable to permit limited relative movement of said corresponding boxedges in a direction perpendicular to the planes of said panels whensaid box sections are fitted in telescoping relation, and locking meansattached for limited sliding movement along opposite sides of one ofsaid box sections adjacent said side edges for movement betweenoperative and inoperative positions, each said locking means comprisinglatch means cooperating with detent means fixed on the other boxsection, said latch and detent means being adapted for lockingengagement to lock said box sections together when said locking means isin said operative position and disengagement when said locking means isin said inoperative position, and cooperating cam surfaces and followermeans on the locking means and said other box section respectively andoperable when said locking means is moved to inoperative position topositively displace said box sections apart within the limits of therelative movement of said hinge means.

2. A radiographic film cassette according to claim 1 wherein one of saidside flanges opposite said hinged edges is cut away to provide anopening for said film and further comprising light-tight sealing meansfor said opening. v

3. A radiographic cassette acording to claim 2, wherein means areprovided to lift the film away from the bottom panel.

4. A radiographic cassette according to claim 3 wherein said filmlifting means are projectable, retractable pins provided incorresponding openings in the bottom panel, said ,pins being retractableto a position flush with the inner face of said panel when said boxsections are in telescoping relation.

5. The film cassette of claim 1 wherein the telescoping side flangesalong opposite side edges of said box 7. The film cassette of claim 5wherein said locking means further comprises an operating armarticulated to each flat bar and pivoted to said one box section forswinging movement between a locking position within said clearance spaceand an unlocking position extending outside said clearance space, eachoperating arm having an extension thereon projecting exteriorly of saidspace when said arm is in locking position to permit the arm to beengaged and operated.

1. A radiographic film cassette comprising two generally flat boxsections, each including a wall panel with side flanges upstanding fromthe edges thereof, adapted to fit together in telescoping relation toform a generally light-tight container, one of said wall panels beingtransparent to X-ray radiation, hinge means connecting said box sectionstogether along corresponding side edges thereof, said hinge means beingyieldable to permit limited relative movement of said corresponding boxedges in a direction perpendicular to the planes of said panels whensaid box sections are fitted in telescoping relation, and locking meansattached for limited sliding movement along opposite sides of one ofsaid box sections adjacent said side edges for movement betweenoperative and inoperative positions, each said locking means comprisinglatch means cooperating with detent means fixed on the other boxsection, said latch and detent means being adapted for lockingengagement to lock said box sections together when said locking means isin said operative position and disengagement when said locking means isin said inoperative position, and cooperating cam surfaces and followermeans on the locking means and said other box section respectively andoperable when said locking means is moved to inoperative position topositively displace said box sections apart within the limits of therelative movement of said hinge means.
 2. A radiographic film cassetteaccording to claim 1 wherein one of said side flanges opposite saidhinged edges is cut away to provide an opening for said film and furthercomprising light-tight sealing means for said opening.
 3. A radiographiccassette acording to claim 2, wherein means are provided to lift thefilm away from the bottom panel.
 4. A radiographic cassette according toclaim 3 wherein said film lifting means are projectable, retractablepins provided in corresponding openings in the bottom panel, said pinsbeing retractable to a position flush with the inner face of said panelwhen said box sections are in telescoping relation.
 5. The film cassetteof claim 1 wherein the telescoping side flanges along opposite sideedges of said box sections are spaced apart to provide clearance spacestherebetween and said locking means comprise elongated flat barsarranged in said clearance spaces, each of said flat bars including aportion projecting exteriorly of said clearance space to facilitateaccess to said bars to operate said locking means.
 6. The film cassetteof claim 5 wherein said flat bars are connected to said one box sectionthrough pin and slot connections.
 7. The film cassette of claim 5wherein said locking means further comprises an operating armarticulated to each flat bar and pivoted to said one box section forswinging movement between a locking position within said clearance spaceand an unlocking position extending outside said clearance space, eachoperating arm having an extension thereon projecting exteriorly of saidspace when said arm is in locking position to permit the arm to beengaged and Operated.